Loan Payoff Time Calculator: Formula, Example and What the Result Means
Works out how long it takes to repay a loan at a chosen monthly payment. This guide walks through what each input means, the formula behind the answer and a worked example using typical Australian figures. You can follow along in the free Loan Payoff Time Calculator.
Why it matters
Personal credit in Australia covers car loans, personal loans, credit cards and buy now pay later. Lenders must quote a comparison rate alongside the headline rate, which bundles most fees into a single figure for a standard loan size.
What you need to enter
The calculator asks for 3 inputs. The table shows each one with the example value used later in this guide.
| Input | Example value |
|---|---|
| Loan balance ($) | 20000 |
| Interest rate (%) | 9 |
| Monthly payment ($) | 500 |
The formula
The balance is reduced month by month: balance + interest − payment.
Worked example
Entering the example values above gives these results:
| Result | Value |
|---|---|
| Time to repay | 4 yrs 0 mths |
| Total interest | $3,867.75 |
The headline figure is 4 yrs 0 mths (time to repay). Change any input in the calculator and every result updates instantly, so you can test different scenarios side by side.
How the time to repay changes with loan balance
The table below keeps every other input at the example value and moves only “Loan balance ($)” up and down by 10% and 20%. It shows how sensitive the time to repay is to that one figure.
| Loan balance ($) | Time to repay |
|---|---|
| 16,000 | 3 yrs 1 mths |
| 18,000 | 3 yrs 7 mths |
| 20,000 | 4 yrs 0 mths |
| 22,000 | 4 yrs 6 mths |
| 24,000 | 5 yrs 0 mths |
At 16,000 the result is 3 yrs 1 mths; at 24,000 it is 5 yrs 0 mths. If a small change in this input moves the answer a lot, it is worth double-checking that figure before you rely on the result.
A practical tip
If the time never ends, your payment is not covering the monthly interest.
Keep going
Before relying on the number, read Loan Payoff Time: What to Check Before You Trust the Number. You might also find these guides useful:
- Using a Credit Card Minimum Repayment Calculator in Australia: A Step-by-Step Guide
- Simple Interest Loan Calculator Explained for Australians
- How the Balloon Payment Calculator Works (With a Worked Example)
Frequently asked questions
- What is a comparison rate?
- It combines the interest rate and most fees into one annual rate, usually based on a $30,000 loan over five years, to make loans easier to compare.
- Do the results include fees?
- Only where a fee input is shown. Add any known fees for a more realistic total.
- Where can I get help with debt?
- The National Debt Helpline (1800 007 007) offers free, confidential financial counselling.
Run your own numbers in the Loan Payoff Time Calculator.
Open the calculatorGeneral information only. Rates and thresholds change, usually on 1 July. Confirm current figures with the ATO or the relevant authority, and get personal advice for decisions about your situation.